Pasta, breads and flours, baked goods, snacks and other cereal-based foods. The scientific study published in Nutrients by the research team led by Professor Enzo Spisni-in addition to exposing the differences between ancient and modern grains-shows the impact of wheat processing method on food quality and consumer health. (1)
Processing processes and human physiology
Since the industrial revolution, the variety of wheat-based foods has increased significantly. (2). Processing processes tend to be more and more invasive and yet they do not seem to fit perfectly with the human organism and its physiological processes, as our bodies are not always able to recognize the resulting products. Therefore, disorders related to the digestion of some wheat-based foods have been attributed to these changes. (3)
In addition to refining, industrial processes applied to wheat include higher dough intensities for bread baking and the use of chemical yeast instead of natural leavening. As well as the increased use of extrusion and high-temperature cooking, which can cause acrylamide formation, among other things. And the addition of vital, or exogenous, gluten.
Milling (or grinding)
Milling is the first transformation process to which grain is subjected. It is mostly made inside cylinder mills that-in the case of refined flour production (type 0 and 00)-mill the caryopses to the point of almost totally depriving them of their fiber and vitamin content, which reside in the wheat germ and are thus removed. Stone millstones are also used, particularly for processing ancient grains into whole grain or low refined flours (type 1 and 2).
Wholemeal and semi-wholemeal flours (type 1 and 2), as it turns out, are enjoying increasing success, especially in Italy. Precisely because there has been increased attention by consumAtors to the health benefits of whole grains. Although baked goods labels are still misleading, as noted, in not a few cases.
Baked goods, leavening, and addition of viable (or exogenous) gluten
Chemical yeasts are often used, in industrial processes, instead of natural yeasts (often designated in ingredient lists as ‘mother yeast,’ which is subject to the labeling requirements for compound ingredients). Natural leavening, on the other hand, increases the digestibility of wheat proteins, including gluten (4) and other proteins with potential inflammatory effects, such as trypsin amylase inhibitors (ATIs). (5). Therefore, natural yeasts have the potential to reduce their immunogenic load.
Viable or ‘exogenous’ gluten can also be added to some baked goods to give them special technological properties. Such as emulsification, cohesion, viscoelasticity, gelling and foaming. Its use has increased by leaps and bounds in recent decades. So much so that it is estimated that ‘exogenous’ gluten intake in the United States tripled between 1977 and 2012, from 140 to over 400 g/person/year. (8)
Bread baking and dough drying
The temperature higher used for industrial processes, such as bread baking or pasta drying, in turn reduces the digestibility of wheat proteins. (4) The most obvious differences, in the processing practices of ancient and modern grains, relate to the invasive industrial processes to which they are often subjected. Ancient cultivars, conversely, tend to be processed using more traditional and less invasive methods. With stone milling and the use–for bread making–of traditional yeasts(S. Cerevisiae). That is, of sourdough, which is rich in lactobacilli and can effectively degrade one of the inflammatory components of the wheat proteome, the ATI proteins. (5)
Baking doughs subject to sourdough seems to reduce the amounts of ATI and FODMAPs(Fermentable Oligo-, Di-, Mono-saccharides And Polyols,). As well as short-chain carbohydrates, which are present in wheat and due to poor absorption contribute to intestinal bloating. (6) On the other hand, modern grains are often refined and used for the production of processed or ultra-processed foods, with added additives and exogenous gluten, which can also drastically worsen their nutritional profiles. (7)
Dario Dongo and Paolo Caruso
Notes
(1) Enzo Spisni, Veronica Imbesi, Elisabetta Giovanardi, Giovannamaria Petrocelli, Patrizia Alvisi and Maria Chiara Valeri. (2019). Differential Physiological Responses Elicited by Ancient and Heritage Wheat Cultivars Compared to Modern Ones. Nutrients 2019, 11, 2879; doi:10.3390/nu11122879
(2) Popkin B.M., Adair L.S., Ng S.W. (2012). Global nutrition transition and the pandemic of obesity in developing countries. Nutr. Rev. 2012, 70, 3-21
(3) Carrera-Bastos, P., Fontes-Villalba, M., O’Keefe, J.H., Lindeberg, S., Cordain, L. (2011). The western diet and lifestyle and diseases of civilization. Res. Rep. Clin. Cardiol. 2011, 2, 15-35
(4) Wu T., Taylor C., Nebl T., Ng K., Bennett L.E. (2017). Effects of chemical composition and baking on in vitro digestibility of proteins in breads made from selected gluten-containing and gluten-free flours. Food Chem. 2017, 233, 514-524
(5) Caminero A., McCarville J.L., Zevallos V.F., Pigrau M., Yu X.B., Jury J., Galipeau H.J., Clarizio A.V., Casqueiro J., Murray J.A. et al. (2019). Lactobacilli Degrade Wheat Amylase Trypsin Inhibitors to Reduce Intestinal Dysfunction Induced by Immunogenic Wheat Proteins. Gastroenterology 2019, 156, 2266-2280
(6) Laatikainen R., Koskenpato J., Hongisto S.M., Loponen J., Poussa T., Huang X., Sontag-Strohm T., Salmenkari H., Korpela R. (2017). Pilot Study: Comparison of Sourdough Wheat Bread and Yeast-Fermented Wheat Bread in Individuals with Wheat Sensitivity and Irritable Bowel Syndrome. Nutrients 2017, 9, 1215
(7) Monteiro C.A., Cannon G., Levy R.B., Moubarac J.C., Louzada M.L., Rauber F., Khandpur N., Cediel G., Neri, D.;L, Martinez-Steele E. et al. (2019). Ultra-processed foods: What they are and how to identify them. Public Health Nutr. 2019, 22, 936-941
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
Agronomist, collaborates with the Department of Agriculture, Food and Environment of the University of Catania, Agronomy and Herbaceous Crops section. Researcher on ancient Sicilian grains.
